Tail gate mechanism for dumping trucks



July '13, 1954 L. s. WOOD TAIL GATE MECHANISM FOR DUMPING TRUCKS Filed July 25, 1951 9 Sheets-Sheet l /0 II IIIIIIII INVENTOR BY mm. MAWM/ IHH Q ATTORN EY y 1954 L. s. WOOD 2,683,545

TAIL GATE MECHANISM FOR DUMPING TRUCKS Filed July 25, 1951 9 Sheets-Sheet 2 INVENTOR 10w; J. W400,

July 13, 1954 .s. WOOD TAIL GATE MECHANISM FOR DUMPING TRUCKS 9 Sheets-Sheet 3 Filed July 25, 1951 L. S. WOOD TAIL GATE MECHANISM FOR DUMPING TRUCKS July 13, 1954 9 Sheets-Sheet 4 Filed July 25, 1951 July 13, 1954 s. WOOD TAIL GATE MECHANISM FOR DUMPING TRUCKS 9 Sheets-Sheet 5 Filed July 25, 1951 INVENTOR ATTORNEY g gi i: \QKMM (WM w y 3, 1954 s. WOOD TAIL GATE MECHANISM FOR DUMPING TRUCKS Filed July 25, 1 51 9 Sheets-Sheet 6 Q mw m 10% d m Wm I INVENTOR l" [OZ/K5 J. -W00fl, BY

ATTORNEY 1954 L. s. WOOD TAIL GATE MECHANISM FOR DUMPING TRUCKS Filed July 25, 1951 9 Sheets-Sheet 7 INVENTOR l aU/f 6. W00,

ATTORN EY TAIL GATE MECHANISM FOR DUMPING TRUCKS Filed July 25, 1951 9 Shgets-Sheet 8 I I I mfi? F 60 /12 {fig/7 :5 V III-v v .r 120; A g INVENTOR H 126" 02035 r 5? 11d a 0. BY 80 0a 7 MW 1.9 4 r ATTORNEY y 3, 1954 1.. s. WOOD 2,683,545

TAIL GATE MECHANISM FOR DUMPING TRUCKS I Filed July 25, 1951 9 Sheets-Sheet 9 w g 16/13: Q Q h ICIIJZE l I INVENTOR LOU/S S. WOOD Y WNW ATTORNE" Patented July 13, 1954 UNITED STATES PATENT OFFICE TAIL GATE MECHANISM FOR DUMPING TRUCKS Michigan Application July 25, 1951, Serial No. 238,443

7 Claims.

This invention relates to tail-gate mechanisms for trucks and the like, and more particularly to a power-operated mechanism of this type whereby the tail-gate is adapted to serve as an elevator for raising a burden from ground level to the level of the bed of the truck body.

My Patent No. 2,469,321 of May 3, 1949, is illustrative of this type of power-operated tail-gate, but in embodiments of that invention the truck body is made fast to the chassis of the truck and is incapable of being pivotally moved into and out of dumping position. Yet there seems to be a demand for a power-operated tail-gate on powerdumped trucks, so it is an object of this invention to devise such an apparatus.

Another object is to arrange the tail-gate operating mechanism so that it will not interfere with the power-operated dumping mechanism for the truck body, and it is a further object to arrange the dumping mechanism including the tail-gate details, so that the truck can dump through the tail-gate when in dumping position without interfering with the tail-gate operating mechanism. In other words, it is an object of this invention to arrange the various mechanisms and the design of the tail-gate itself so that the power-operated tail-gate can operate satisfactorily when the truck body is in nondumping position while the truck body dumping mechanism can work and the truck load can dump or cascade through a port in the tail-gate when the truck body is in dumping position and the tail-gate mechanism is inoperative.

It is a still further object of this invention so to arrange and construct the parts that when in load-dumping position, the tiltable body clears all of the operating parts and yet is depressed so that when in dumping position, the dumping end of the body is much nearer the ground than when in non-dumping position.

It is another object of the invention to provide a novel mechanism for automatically holding the control lever and associated mechanism in operative position as desired until mechanically or manually changed. Utilizing such novel mech anism eliminates the necessity of having to hold the control lever when operating the tail-gate.

With the above and other objects in view, the invention consists in the construction and novel combination and arrangement of parts hereinafter fully described, illustrated in the accompanying drawings and pointed out in the claims hereto appended, it being understood that various changes in the form, proportions, and minor details of construction, within the scope of the claims, may be resorted to without departing from the spirit or sacrificing any of the advantages of the invention.

In the drawings- Fig. 1 is a side elevation of the rear portion oi a dumping truck, showing the dumping body in a horizontal position and the tail-gate lowered to the ground in position to receive a load to be transferred into the body of the truck;

Fig. 2 is a similar view showing the tail-gate elevated and in a horizontal position contiguous to and flush relation with the floor of the body of the truck;

Fig. 3 is a side elevation showing the tail-gate closed and latched; v

Fig. 4 is a similar view showing the dumping body tilted for dumping and the port-gate of the tail-gate open to permit the contents of the dumping body to cascade through the tail-gate;

Fig. 5 is a rear elevation of the dumping truck, parts being broken away to illustrate the tailgate operating mechanism more clearly;

Fig. 6 is a side elevation on an enlarged scale showing the rear portion of the truck with the tail-gate arranged as shown in Fig. 1;

Fig. 7 is a similar view with the tail-gate arranged as illustrated in Fig. 2;

Fig. 8 is a similar view on an enlarged scale taken from the other side of the dumping truck, parts being broken away for clarity of illustration;

Fig. 9 is a perspective view of the rear portion of the dumping truck with the parts arranged as shown in Fig. 1;

Fig. 1G is an enlarged detail sectional view illustrating the means for holding the dump portgate in its closed position;

Fig. 11 is an enlarged detail perspective view illustrating the latching assembly for locking the dump port-gate in its closed position;

Fig. 12 is an enlarged plan View illustrating the mechanism for operating the tail-gate, a portion of the truck body being shown in dotted lines;

Fig. 13 is a detail vertical sectional view taken on the line 13-43 of Fig. 12;

Fig.- 14 is a similar view taken on the line i i i of Fig. 12;

Fig. 15 is an enlarged detail view of the catch controlling mechanism for locking and unlocking the lifting arms of the tail-gate;

Fig. 16 is an elevational view partly in section, illustrating an adjustable pre-loaded valve centering mechanism for holding the valve in a desired operating position until manually or mechanically released;

Fig. 17 is an end elevation of the mechanism shown in Fig. 16.

In the accompanying drawings, in which is illustrated one embodiment of the invention, the dumping truck is provided with a dumping body I provided at opposite'sides of :its rear end with depending bearing brackets 2 constructed of any suitable material such as flanged metal, consisting of a vertical upper oblong portion 3 and a tapered inclined lower portion :extendingdownwardly and forwardly and provided at its lower end with a bearing 5. The bearings of the brackets 2 receive and have .journaled in them for rotary movement an outer transverse shaft 6 which has journaled within it for rotary movement an inner transverse shaft 1. The outer transverse shaft '5 is journaledinlsuitable bearings 8 of bearing brackets 9 located at opposite sides of the truck and secured to the chassis thereof and the lower portions ll of the bearing brackets 9 extend downwardly and forwardly at an inclination from the upper attached portions l2 of the bearing brackets fl.

The dumping body which pivots on the outer s'haftt is tilted from the horizontal position illustrated in Figs. 1 to 3, inclusive, to the inclined position shown in Fig. 4 by the usual hydraulically operated means including spaced cylinders l3 located at opposite sides of the chassis of the truck and arrangedat an inclination and pivoted at their lower ends at I4 to depending bearing brackets i5 secured to the chassis of the truck, as clearly illustrated in Figs. 1 to l, inclusive. The piston it of each cylinder is is pivotally connected at E5 to the dumping body at the bottom thereof below the upper face of the floor of the same. The hydraulic power means for operating the dumping body is of the usual conventional means and is valve controlled within the cab of the truck and further illustration and description of the power means for operating the dumping body are believed to be unnecessary as the dumping body operates in the usual manner and is tilted from its normal horizontal position to an inclined dumping position and automaticall-y returns to its initial horizontal position after the discharge -of its contents when the piston i5 is relieved of hydraulic pressure in the usual manner.

The particular means for pivotally mounting the dumping body is important as the dumping body is pivotally supported from the same duplex shaft that depends from the chassis and not from the body, consisting of the inner shaft 1 and the outer shaft 6 and from which the tail-gate I! is entirely operated in all of its positions and about which the body 1 is tilta-ble or dumpable. Also but secondarily important are the construction and arrangement of the brackets which tiltably support the rear end of the dumping body from said shaft whichpermit the body when in dumping position to clear the other parts of the truck, whereby the dumping end of the body can closely approach the ground.

Details of tail-gate raising and lowering mechanism While the invention is directed primarily to a power-operated tail-gate capable of being applied to a dump-body and provided with an independently operable dumping inner or port-gate i8 in the main tail-gate l1, it also includes a number of features that cooperate to make such a combination operable satisfactorily. In my preferred embodiment of this invention the tail-gate 4 raising and lowering mechanism on the one hand and on the other hand the tail-gate operating mechanism to move it between the horizontal and vertical positions, both function from said duplex operating shaft that has one shaft concentrically arranged withinthe other in a way that rotation of the outer shaft causes the raising and lowering of the power tail-gate while the rotation of the inner shaft causes movement of the tail-gate between the horizontal and vertical. So, in obtaining the object of this invention, this duplex shaft that extends transversely of the truck must be operative-1y supported from the truck chassis .atanelevation below the top of the chassis and sufficiently inboard from the tailgate so that there is no interference of these mechanisms with the full dumping operation of the truck body and the tail-gate. This is accomplished by the angle or knee-shaped brackets 2 which must be long enough to provide for the support of a cylinder 1-9 and its mechanism for swinging the tail-gate between horizontal and vertical while at the same time making unnecessary too long a reach between the inner of the concentric shafts and the tail-gate.

The outer shaft is provided at its central portion with a of arms 2e extending upwardly and rearwardly at an inclination when the tailgate is in its lowered position, as illustrated in Figs. 6 and 9, and Pear g secured between their outer ends by a pivot 2i the outer end of a pisten '22 or" a cylinder 23 arranged at an inclination and extending downwardly and rcarwardly from the truckbody l and connected at its upper end to the same by a suitable pivot 24 at a point below the upper face of the bottom of the truck body.

She outer shaft 6 is also provided adjacent its ends with a pair of lifting arms 25 rigidly connected with the outer shaft 5 which preferably comprise I-beams or other suitable material having the required strength. The lifting arms 25 are provided at their outer ends with plates 25' rigidly secured to the lifting arms in any suitable manner and connected at their outer ends with the tail-gate adjacent the lower edge thereof by a pivot 25. When pressurized fluid is introduced into the cylinder 23 for actuating the piston 22, the outer shaft is rotated for oscillating the l iting arms 2% and lowering the tail-gate while horizontal from a position level with the floor of the truck body to the ground or for elevating the tail-gate to return it while still horizontal from its ground position to its elevated position flush with the :door of the body l of the truck and thus enabling a load to be lifted from the ground and readily transferred into the truck body. The lifting arms 25 swing, through an are indicated by the d0tand-dash line 2? of Fig. 6 and the tailgate is carried in a substantially horizontal position from one point to the other and vice versa. Therefore it constitutes a pla form on which th operator may stand while the load is being transferred from the ground to the body of the truck or from the truck to the ground.

Tail-gate swinging mechanism and operation The pivot 25 prefe ably consists of a transverse shaft journaled in suitable eyes 28 of the tailgate and it constitutes a pintle on which th tailgate swings in lowering it from a vertical closed position indicated by dotted lines in Figure 7 to the open horizontal position shown in full lines in this figure of the drawing. The ends 29 of the inner shaft 1 are extended beyond the ends of the outer shaft '6 and are provided with terminal oppositely extended radially disposed arms 3b which are connected by pivots 3! to the adjacent ends of the pair of spaced parallel links 32 preferably consisting of flat bars connected by pivots to the hinged lower or inner edge of the tailgate at opposite sides of the pintle or pivot shaft 25. The inner shaft is adapted to be rotated to carry the arms 3!] through an arc of approximately 45 and this motion is transmitted by the parallel links 32 to the tail-gate which is adapted to be swun downwardly from the vertical dotted line position shown in Fig. 7 to the horizontal position illustrated in full lines in said figure and also to be swung upwardly from the full line horizontal position shown in Fig. '7 to its vertical closed position illustrated in dotted lines in said figure. Any other suitable link connection may, of course, be provided for transmitting motion from the inner shaft to the tail-gate and swinging the gate on its horizontal shaft or pintle 26.

rotary movement of the inner shaft 7 is effected by a piston 3 operating in the cylinder is extending longitudinally of one of the angle bearing brackets 2 of the body I and arranged at a slight inclination and connected at its upper end by a suitable pivot 35 to the bracket 2 on which it mounted. The lower end of the piston 3-: is connected by a pivot 36 to an angle arm 3? fixed to the adjacent outer extended end of the inner shaft 7 and extending downwardly rearwardly therefrom, as clearly illustrated in Fig. '7 of the drawing.

The tail-gate ll and the dump or port-gate i8 are operable as a unit in swinging the tail-gate from a vertical to a horizontal position to open it,-and also when lowering the tail-gate from an elevated horizontal position contiguous to the floor of the body of the truck to the ground and while elevating the tail-gate to said horizontal position and also while swinging the tail-gate from said horizontal position to its vertical closed position. The tail-gate unit comprises a frame composed of spaced parallel side portions 38 and a connecting bottom portion 39 and the dump or port-gate 55 consists of a panel connected at its upper edge to the upper ends of the sides 38 by suitable pivots 36, but the panel may be pivoted. within the frame of the tail-gate in any other suitable manner. The inner ends of the sides and the lower edge of the connecting bottom portion of the frame of the tail-gate are a1 flush with the inner faces of the side walls of the body and the bottom of the body when the tail-gate is closed so that when the body is tilted to its dumping position and the port-gate is unlatched. the entire contents of the body of the truck may be discharged through the opening in the tail-gate without any interference by the frame of the tail-gate of the complete discharge of the contents of the truck.

system and valve control mechanism A hydraulic pump. not shown, adapted to be driven by any suitable means, as by the motor of the truck, is connected to each of a pair of hydraulic valves ii and 62 shown in Figures l2, l3 and 14 and supported by a transverse frame member as secured to laterally spaced longitudinal fram members 44. The valve 4| com municates by hydraulic lines 45 and 46 with the spaces between the ends of the cylinder l9 and the piston 36 which is connected to the inner 6 shaft 1. The other valve 42 is connected by the hydraulic lines 41 and 48 with spaces between ends of the cylinder 23 and the piston 22 which is connected with the outer shaft 6.

The valves GI and 42 which may be of any preferred type are preferably constructed substantially the same as those shown and described in said Patent 2,469,321, and when the valve stems 49 and 50 are moved inwardly to the limit of their inward movement they open the valves to connect the cylinders l9 and 23 to the pump and when the valve stems are carried to the limit of their outward movement communication between the cylinders 59 and 23 through the hydraulic lines 45 and 48 with the pump is cut off and the hydraulic lines are placed in communication with a sump for exhausting pressurized fluid from the cylinders and at the same time admitting pressurized fluid to the other end of the cylinder [8 through the hydraulic line it for returning the piston to its initial position. The valves, as ex plained in said patent, may be moved to a position effective to disconnect the pump from the cylinders I9 and 23 and maintain a fluid loci: within the cylinders.

It will be understood, as explained in said patout, that the operation of the valve :2 prevents any passage of fluid to the valve ii. The stem 49 of the valve 4! may be moved inwardly simultaneously with a similar movement of the stem 56 of the valve 42, but it is only upon outward movement of the latter stem to its outward position that pressurized fluid may now through the valve to the cylinder 23. Thus the cylinders it and 23 may be operated independently of each other but not simultaneously.

The valve stem 69 is connected by a link rod 5| with an arm 52 of a transverse control or operating rock shaft 53 journaled in suitable bearings of the frame of the truck body extending transversely thereof from one side of the truck body to the other side of the same and provided at each end with an operating handle 5&. The operating handles 54, which are approximately L- shaped, extend at each side of the truck body to points within easy reach of a person standing at the side of the truck.

The valve stem of the valve 32 is connected by a link rod 55 with an inner depending arm 56 of a transverse rock shaft 57 journaled in suitable bearings of the truck body frame and pro vided with an outer depending arm 58. The outer depending arm 53 is connected by a link rod 59 with a depending arm 68 of an operating shaft 6| journaled in suitable bearings of the frame of the truck body and extending across same and provided at each end with an upwardly ex tending operating arm or handle 62. The control mechanism for operating the valve stem Eil of the valve 42 is adapted to be operated from either side of the truck.

When the control valve 42 is operated to introduce pressurized fluid into the cylinder 23 for elevating the tail-gate from the ground position shown in Fig. 6 to the dotted line position illustrated in said figure, wherein the tail-gate is still in its horizontal position but flush with the floor of the body of the truck, the tail-gate lacing automatically stopped in the dotted line position by means operable by the outer shaft 6 to which the lifting arms 25 are connected. The rock shaft 5! is slidably held in the guide member 363 through which the front end of the rod iti passes, as shown in Fig. 13. The rear end of the rod 10] is connected to a crank arm I94 arranged in an upright position on the shaft NW which is suitably journaled in body hinge. The rod HH and the arm [M are movable rearwardly from the position illustrated in Fig. 13 of the drawings. Adjacent the arm HM and carried by the shaft 64 is an adjustable abutment screw H5 which is contacted by one of the lifting arms 25 when the gate reaches the raised horizontal position shown in Fig. 7. The shaft 05 is rotated coun erclockwise upon the lifting arm striking the screw I 15. This causes forward movement of the rod it! beyond the position illustrated in Fig. 13 for enabling the coil spring I to bias the arm 6'? and the rock shaft in the position illustrated in Fig. '7. The, spring permits rearward movement of the arm 61 and partial rotation of the rock shaft 5? from the position illustrated in Fig. 7 in the operation of the valve 62. The spring I00 and the red It are adapted to yield to the movement of the arm 5'! when the handle lever 62 is operated. Adjustment of the abutment screw H5 is made so that it will be engaged and the rod in! actuated to shut off the flow of pressure fluid to cylinder 23 whereby the tail-gate is accurateiy aligned with the floor of the truck when in its raised position as shown in Fig. 7.

The lifting arms 25 are provided at their outer portions adjacent the tail-gate with lugs 1% arranged to be engaged by a pair of pivotaily mounted gravity acting catches 86 arranged in the path of the lugs I5. When the lifting arms are swung upwardly to a vertical position they are automatically locked in such position to prevent the tailgate from dropping should there by any release or failure of the hydraulic means. When the ta l-gate is swung upwardly from its elevated horizontal position flush with the floor of the truck body to its vertical closed position it is automatically locked in such closed position by a pair of catches 8i located at opposite sides of the truck body exteriorly of the sides thereof and extending through guides 82 and arranged to engage shouldered lugs 83 located at the opposite side edges of the tail-gate at the upper port-ions of the sides 38 of the frame of the tailgate. This assures positive support for the gate when dumping. The catches are pivoted at their inner ends 8:; to operating levers 85 at points intermediate of the ends thereof. The operating levers B5 are pivoted at the inner ends to the truck body exteriorly of the sides thereof and their outer portions form handles for manually operating the catches 8!.

Also when the tail-gate is swung upwardly to the vertical position, the forward flange 80 comes to rest on lange of angle bracket se to prevent lowering tail-gate in vertical position.

Rock shaft 53 is provided with a pair of oppositely extending arms 68 and 88 pivotally connected at If! and H to the upper ends of a pair of operating rods T2 and ":3 having their lower end portions slidable in guides 14 and I5 carried by one of the bearing brackets 2 and arranged to be engaged by lugs it and Ti projecting radially from the outer shaft 5. As the tail-gate approaches its vertical position the lug 16 engages the lower end of the operating rod 13 and shifts the rock shaft 53 so as to operate the valve M and cut off pressure fluid to prevent further movement of the tail-gate. Also when the valve 49 is operated to open the tail-gate from the dotted line position shown in Fig. '7 to the horizontal position, the lug ll of the outer shaft 5 engages the lower end of the operating rod 12 and operates the valve 4! to prevent further rotary movement of the outer shaft. The operating rods 12 and T3 are provided at their upper ends with sections 18 having a threaded connection with the rods for adjusting the same for enabling the valve 4| to be accurately operated.

The dump port-gate I8 is held in its closed position by one or more arms 86 of a rock shaft 8'! journaled in suitable bearings of the transverse connecting portion of the frame of the tail-gate and provided adjacent to one side thereof with an interiorly arranged radially projecting plate 88 fixed to the rock shaft 87. The dump port engaging arm is movable inwardly and outwardly through a slot 89 in the transverse connecting portion of the frame of the tail-gate to engage it with and disengage it from the dump port-gate and the arm 36 is locked in engagement with the dump port-gate by means of a locking member 2i} consisting of a rod slidably mounted in the frame of the tail gate and provided with an approximately L-shaped arm 9| having its terminal portion or bill 92 extending into the frame of the tail-gate and arranged to engage an opening 93 in the plate 38 of the rock shaft 81. The L- shaped arm 9! provides an exteriorly arranged loop forming a handle or grip adapted to be readily grasped by the operator for withdrawing the terminal engaging portion 92 from the opening 93 in the plate 88 of the rock shaft 8'1. When the terminal portion 92 of the locking member is engaged with the opening 93, the rock shaft 81 is held against rotation and the arm 83 is maintained in engagement with the dump port-gate. The locking member 98 is urged inwardly by a coil spring 9 which maintains the terminal portion 52 in engagement with the plate "8 of the rock shaft 8?. The coil spring is interposed between a portion of the frame of the tail-gate and the collar 95 or other abutment provided on the inner end of the rod portion of the locking member til.

The rock shaft 8? is provided at one end adjaoent the locking member 98 with an exteriorly arranged arm. 95 which is connected by a link 91 with an angle lever 98 pivotally mounted at 99 on the frame of the tail-gate. The outer portion of the angle lever forms a handle and the angle lever through its link connection with the arm 96 of the rock shaft 81 is adapted to partially rotate the rock shaft to carry the locking arm 8'? to and from its position in engagement with the dump port of the tail-gate.

Details of kick-out valve control mechanism and operation The control mechanism for the valves 41 and 1.2 includes a so-called kick-out lever release means, as illustrated in Figs. 16 and 17. This mechanism is operatively connected at one end of the valve assembly to a rod which controls the setting of the valve ports, and is illustrated in Fig. 16 in connection with the operation of valve :52. It will be understood that valve Al is equipped with a similar kick-out control mechanism as for valve 52 and operates in the same manner. The mechanism as illustrated in Fig. 16, comprises an elongated tubular housing 25 having a central bore l2! extending lengthwise therethrough and arranged to slidably receive a shaft I22. The shaft 22 extends outwardly from the housing I20 and is attached at its outer end through an arm 2 to the opposite end of the valve shifting rod 5%, as shown at I 26. The shaft 22 comprises a reduced diameter portion 528 which extends through an enlarged diameter spring chamber [36. A coil Spring iSl urrounds the reduced diameter shaft portion i and is retained under compression between the washers E32 and I33. The washers are slidably fitted in the chamber i233 and are adapted to be moved axially of the shaft to compress the spring iti upon shifting of the shaft i222.

On the outer end of the reduced diameter portion i -i of the shaft a sleeve lfi i is mounted and which is adapted to slide in the bushing F33 which is secured in the end portion of the spring chamber i323. A stub bolt I l-t is received on the outer end or" the shaft and is threaded down against a washer it! whereby the sleeve 36 is retained in place on the shaft between the washers i33 and ML On the enlarged diameter portion of the shaft E22 there is provided spaced circumferential grooves Hi6 and t ll which are adapted to receive a spring-pressed ball detent lei). spaced grooves or indentations for receiving the ball E cooperate with the setting of valve rod 526 so that the valve positions correspond to the spaced groove sections on the shaft 522. The ball detent mechanism comprises a tubular casting it? which is threaded into the body of the house-g adapted to contain a coil spring for varying the load on the ball I56. lower end of the spring I54 restson the ball detent the ball being of a diameter to fit snugly into the annular grooves E 35, ME, if. To provide for adjusting the spring load on the ball detent the upper end of the casing 152 is threaded to receive a hollow set screw member itii which may be threaded downwardly to vary the load on the coil spring le t. The upper end of the casing 5.2 of the ball detentmechanism is suitably closed by a cap ifiii which is threaded on the end of the casing, as illustrated in Fig. 16. A grease cup it! is suitably mounted on the cap 266 for conveniently applying lubrication to the ball detent iilfi.

1e valve kick-oat lever release assembly is iy supported on the spaced leg members which in turn are welded to the lower portion of the casing lit. The leg supports I55 are adapted to rest on a base plate MB suitably nounted on the top of the valve assembly 42, as .lustrated in Figs. 16 and 1'7.

The setting of the rod lit, which is operatively connecte to the rod and forms an extension thereof, is yieldably maintained in either one of three positions by the adjustable spring loaded bail detent Thus when the valve rod 59 and its counterpart are shifted as by manually moving the lever 2, so as to slide the valve rod, for instance, to the left, as seen in Figs. 13 and the arm iZ attached to the end of the rod detent 558 is forced out of its center groove ition, representing the neutral or fluid lock ion, upon further movement of the shaft E22, drops into the annular groove Ml, where the parts are maintained during the operation of the hydraulic lift. The spring I5 2 of the ball detent is adjustably loaded, as aforementioned, by turning down the screw member i58 so that the spring load on the ball detent is just sufficient to overcome the force exerted by the compression spring Edi and which tends to return the shaft it? to its center or fluid lock, safety position. Under this action of the spring loaded ball detent, it is unnecessary for the operator to hold his hand on the control lever for operating the hydraulic valves after the lever is moved either The p 10 to the right or left, to start the desired power movment of the tail-gate mechanism.

At the end of the particular cycle of operation initiated by movement of the lever 62 or 54, the valve control rod to which the hand lever is operatively connected is manually shifted or mechanically engaged so tha the ball detent its is forced out of its seat in the groove and the spring I38 is then permitted to return the shaft I22 to its normal center groove which represents the fluid lock, safety position. In this position all movement of the parts is stopped instantl and maintained in their relative positions. This kick- 01117 mechanism thus provides fingehtip control so that the tail-gate can be stopped instantly and at any intermediate position desired.

A coil spring [00 mounted on a rod Hit and interposed between a collar I02 on the rod and an arm member 6's of the rock shaft ill permits lost motion between the parts-whereby themanually operated control lever 62 can remainin a set position until manually moved or its connecting control rod mechanism shifted automatically by engagement therewith of a portion of the tail-gate mechanism being moved to thereby cause the shaft I22 to shift and release the ball detent from the operative position whereby the same is shifted by the coil spring is; to its neutral, fluid lock, safety position and all movement of the parts ceases. llhe same action takes place upon actuation of the control lever as which is also provided with a similar spring actuated ball detent kick-out lever release mechanism and as shown in Fig. 14 by-the prime reference characters and corresponding to the reference characters designating the described parts for operating the valve 32.

The catches 89 which arelocated at opposite sides of theframe of the truck body, are-mounted on short shafts 1B8 journaled in suitable bearings of brackets I09 and provided with arms l 16 which are connected by short links ill to arms ll? of a transverse rock shaft -l l3 which is connectedby a link rod H4 with the arm -57 of the rock shaft 51 whereby the catches fill will be lifted out of engagement with the lugs 79 by operation of the lever 62.

While the preferred embodiment of the invention has been shown and described, it is -to be understood that this embodiment may be modified as to the details within the spirit and scope of the invention and as covered by the appended claims.

I claim:

1. A tail-gate mechanism for association with a fioor-bearing pivoted dumping body supported from a truck chassis, having a composite tailgate assembly of a tail-gate and a port-gate pivotally supported from the tail-gate, independent means for operating the port-gate alone, and dual means connected with the tailgate for operating the assembly as a unit comprising a power-operated mechanism for raising and lowering the assembly between ground level and the level of the body floor and another poweroperated mechanism for pivotally moving the assembly back and forth between the horizontal and the vertical, the mechanisms each including a horizontal shaft extending transversely of the truck with the said shafts being concentrically mounted one within the other, a pair of brackets depending from the chassis while reaching forwardly of the truck and rotatably supporting the outer shaft, another pair of brackets depending from the body and reaching forwardly of the truck and pivotally supporting the body from the outer shaft, a power cylinder depending from the body and connected with the outer shaft, and a power cylinder supported from one of the body brackets and connected with the inner shaft.

2. Apparatus according to claim 1, wherein the power cylinder for moving the tail-gate between the horizontal and the vertical i connected with the inner shaft by a connection that positions the cylinder to the rear of its shaft.

3. Apparatus according to claim 1, wherein the power cylinder for raising and lowering the tailgate up and down is connected with its shaft by a connection that positions the cylinder forward of its shaft.

4. Apparatus according to claim 1, wherein thc mechanism for moving the tail-gate between the horizontal and the vertical includes a pair of superposed links extending between its shaft and the tail-gate frame with the links of each pair being pivotally secured to the frame at spacedapart points.

5. A dumping truck including a chassis, a dumping body, a tail-gate for the dumping body having a dump port-gate pivoted thereto and movable from a closed position to an open position for the discharge of the contents of the dumping body, a releasable latch for the portgate, an outer shaft and an inner shaft concentrically arranged one within the other and carried for rotation by said chassis, means for pivotally connecting the rear end of the dumping body with said outer shaft, mechanism connected with the chassis and the dumping body for dumping the latter, at least one lifting arm having a fixed connection with said outer shaft and a pivotal connection with said tail-gate adapted to raise said tail-gate upon rotation of said outer shaft, and means for connecting the tail-gate with said inner shaft for effecting swinging movement of the tail-gate.

6. A dumping truck including a chassis, a dumping body, a tail-gate for the dumping body having a dump port-gate carried thereby and movable independent of the tail-gate to an open position for the discharge of the contents of the dumping body, latch means releasably holding said port-gate closed, an outer shaft and an inner shaft concentrically arranged and carried for rotation by said chassis, means for pivotally connecting the rear end of the dumping body with said outer shaft, mechanism connected with the chassis and the dumping body for dumping the latter, at least one lifting arm having a fixed connection with said outer shaft and a pivotal 12 connection with said tail-gate adapted to raise said tail-gate upon rotation of said outer shaft in one direction, and means including parallel link bars connected with said inner shaft and with the tail-gate for effecting swinging movement of the latter.

7. A dumping truck including a chassis provided at its rear end with depending bearing brackets, an outer transverse shaft journaled in the bearing brackets of the chassis and provided with at least one lifting arm extending rearwardly from said shaft, a dumping body provided at the rear end with depending bearing brackets having downwardly and forwardly extending lower portions journaled on said shaft for pivotal movement of the dumping body, power means connected with the chassis and the dumping body for dumping the latter, a tail-gate pivotally connected with said lifting arm and provided with a dump-port-gate openable to provide an opening in the tail-gate for the discharge of the contents of the dumping body, an inner shaft journaled for rotary movement within the outer shaft, power actuated means for connecting the tail-gate with the inner shaft for swinging the same on its pivotal connection with the lifting arm to carry the tail-gate from a vertical closed position to an open horizontal position and for returning the tail-gate to its closed position, and separate power actuated means for rotating the outer shaft for raising and lowering the tailgate while the tail-gate is in a horizontal position.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,376,733 Sanderson May 3, 1921 1,458,240 Otterson June 12, 1923 1,481,538 Crooke Jan, 22, 1924 1,790,379 Hughes Jan. 27, 1931 1,883,473 Barrett Oct. 18, 1932 1,983,051 Smith Dec. 4, 1934 2,037,999 Ochsner Apr. 21, 1936 2,136,010 Housdorfer Nov. 8, 1938 2,201,148 Berger May 21, 1940 2,246,358 Jelinek et al June 17, 1941 2,261,099 Fairbanks Oct. 28, 1941 2,285,655 Heinemann June 9, 1942 2,410,046 Burns Oct. 29, 1946 2,469,321 Wood May 3, 1949 2,480,528 Wachter Aug. 30, 1949 2,512,320 Fischer June 20, 1950 2,522,441 Galloway et al. Sept. 12, 1950 2,593,240 Anthony et a1. Apr. 15, 1952 2,645,522 Kersey July 14, 1953 

